Green's theorem applied to polar graph

csnsc14320
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Homework Statement



Use Green's theorem to compute the area of one petal of the 28-leafed rose defined by r = 5sin(14 \theta)

Homework Equations


A = \frac{1}{2} \int_c{x dy - y dx}
\int \int_c{M_x + N_y}dx dy


The Attempt at a Solution



I'm really more confused about just what to do outright. Green's theorem tells me that I can take the integral in that area formula and compute the double integral of the divergence of a vector field F = <M(x,y),N(x,y)>, but I have no idea how that helps me since I don't see any vector field here and I don't know the components N and M.

I think maybe I need to turn the expression r = 5sin(14 \theta) into cartesian coordinates, but not really seeing what to do from here.

theres just too many equalities in greens theorem >:(
 
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Hi csnsc14320! :wink:

(your equations look a bit odd)

Hint: you're looking for a function whose curl is constant. :smile:
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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